Some of electronic devices have communication functions, and have been manufactured and sold with sizes small enough to be carried. Recently, with the aid of hardware and software supports, such electronic devices have been dramatically grown.
Portable electronic devices among electronic devices use a mobile communication network system using a base station so as to support a communication function as well as mobility. In order to use the mobile communication network system, it is required to design and install a base station, a base station controller, and a mobile switching center, which constitute the system.